Want to trip out your brain for a few minutes? Watch OK Go's new music video for their song "The Writing's on the Wall" and delight in what you can do with mirrors, paint, and objects in the proper position. »6/17/14 3:35pm 6/17/14 3:35pm

Take a peek at Deformscape, a garden patio in San Francisco. The architectural sculpture is a practical solution to limited space, and a vertigo-inducing illusion of a wormhole ready to suck the neighbourhood into the Japanese Maple tree. »3/24/14 12:39pm 3/24/14 12:39pm

The best optical illusions are often the ones we happen upon unintentionally, which is exactly what happened when redditor Liammm decided that water circling the drain of his sink would make for a nice photographic subject. »11/13/12 8:10am 11/13/12 8:10am

This optical illusion is a fairly simple one, but it's still a very impressive effect. A triangle and some cunningly positioned diagonal lines are all that's needed for your brain to tilt a perfect level rectangle completely off-kilter. »4/29/12 3:30pm 4/29/12 3:30pm

At first glance, this looks like a poster for Harry Potter, but is there something more going on? These posters illustrate famous stories with minimalist images, but hide a second story inside. »4/14/12 8:00am 4/14/12 8:00am

You've probably seen this optical illusion before, in which two lines of identical length appear to be different by adding opposite-facing arrows to them. It's a very powerful effect - so much so that it overwhelms all other visual information. »12/07/11 10:20am 12/07/11 10:20am

The Motion Aftereffect is an optical illusion in which stationary objects appear to be in motion if a person has just been looking at a moving background. And the effect appears to work on the deepest levels of our subconscious. »6/28/11 12:34pm 6/28/11 12:34pm

Imagine that you woke up to discover you had somehow shrunk to a doll's size. Would you think you were tiny...or that everyone else was a giant? Some Swedish psychologists decided the world deserved an answer to that age-old question. »5/26/11 9:30am 5/26/11 9:30am

It turns out that the impossible buildings and bizarre objects dreamed up by artists like M.C. Escher tap into an incredibly primal understanding of the world's geometry, a knowledge that is hard-wired into all vertebrates, including newly hatched chickens. »3/28/11 1:00pm 3/28/11 1:00pm

A recently released video shows what seems to be two suns setting in China. This strange, otherworldly sight could just be a hoax, but similar optical illusions have been seen before. The only problem is we still haven't explained them. »3/06/11 3:00pm 3/06/11 3:00pm

These pictures offer a spectacular view of the rising Moon from the International Space Station. But look closely at the Moon in these photos and you can see how it appears to be strangely squished. What's causing this weird effect? »1/23/11 7:30am 1/23/11 7:30am

"Impossible Motion: Magnet-like Slopes" won the 6th Annual Best Visual Illusion of the Year competition, held in Florida a few days ago. And, much like yesterday's street paintings, it will make your brain hurt. »5/11/10 5:00pm 5/11/10 5:00pm

Yesterday, Saturn reached its equinox, an event that occurs once every 15 years that creates the illusion that its rings have disappeared. The Cassini spacecraft was there to capture rare images of an apparently ringless Saturn. »8/13/09 12:23pm 8/13/09 12:23pm

Bad weather has trapped you in the house, and it's getting darker outside every day. You're feeling depressed and crazy. What you need is a dose of dystopian cinema that's all about how the dark world you inhabit is just the product of some AI's fevered imagination. io9 always wants to make you feel worse, so we've… »12/04/07 2:30pm 12/04/07 2:30pm